Stuffer-box crimpers



y 1966 A. STEPHENS ETAL 3,249,979

STUFFER-BOX CRIMPERS Filed June 29, 1964 wii /mw A ttorneys United States Patent 3,249,979 STUFFER-BOX CRIMPERS Allan Stephens and James Brebner, Doncaster, England, assignors to British Nylon Spinners Limited, Pontypool, England a Filed June 29, 19 64, Ser. No. 378,800 Claims priority, application Great Britain, July 6, 1963,

3 4 Claims: c1. 28-1) The invention concerns improvements in, or relating to stufferbox crimpers.

Stuffer-box crimpers have been in use for very many years for imparting crimp to textile tows and slivers; and more lately they have been employed for the crimpingof yarns.

In most constructions of such stulfer-box crimpers, a

' pair of driven stainless steel nip rolls, of a width roughly equivalent to that of, say, a tow to be crimped, serve as the feed for, and one end-closure of, a compression chamber fitting close into-the nip of said rolls. The compression chamber usually consists of front and back plates in the plane of the nip rolls, one of said plates being provided with a hinged flap, and shoe plates separating said front and back plates and in close proximity to the cylindrical surfaces of the nip rolls in the fashion of scraper blades. At the nip of the rolls, provision is drical faces of the rolls themselves. Insofar as the disc inserts have been in contact with cooled parts of the st-uifer-box or with water supplied to the rolls, they themmade in the front and back plates-to hold replaceable hard-wearing materials, such as vitreous, ceramic or metal materials; and one type of material currently in use for the contact surface with the nip rolls is Phosphor bronze.

The whole assembly of rolls and plates is held firmly together at the nip of the rolls by the application of pressure to the disc inserts, such pressure being applied to the disc on one side by a screw projecting through an arm which is pivotally mounted at one end to the frame of the crimper and detachably secured at the other end to the frame. The arm serves as a gate by which the mechanism can be locked for operation or unlocked for inspection or replacement of parts. The disc on the other side is a firm fitting against the frame.

During operation, owing to the heat of work in-crimping and owing to the frictional contact between the bearing surfaces between the sides of the rolls and the parts of the compression chamber, even with lubrication thereof, the walls and rolls of a stuffer-box crimper heat up.

In particular, the stationary disc inserts tend to heat up considerably, owing to their position and function and to their relative inability to lose heat to the surrounding atmosphere compared with the ability in this respect of the rolls themselves.

Eflicient lubrication of the bearing surfaces between the rolls and disc inserts helps to control the heating of the disc inserts, but despite this, we have found that the disc inserts may sometimes attain a temperature which is higher than the fusion temperature of the material of the tow or yarn being processed. For instance, the fusion temperature of Nylon 66, polyhexamethylene adipamide, is around 250 C.; and if the disc inserts, being of Phosphor bronze, exceed that temperature, the result is that the front and back edge filaments of a filamentary tow of Nylon 66 may become fused, and the crimped tow product thus has to be downgraded for this damage to a mere minor proportion of its filaments.

Efforts to cool parts. of the compression chamber of a stuifer-box have been made before, as also have efforts to cool the rolls by a supply of water as a lubricant to the faces of the rolls or as a drip supply to the cylinthe frame 5 of a stuffer-box crimper head.

selves have been cooled slightly by such contacts. But so far as we are aware, no previous attempt has been made deliberately to cool the inserts specifically. Furthermore, the provision of external water necessarily has the effect of increasing the moisture content of the tow, sliver or yarn, which increase not only alters the conditions of crimping, but also may mean that the crimped product will be outside the required specification for moisture content. ter that can be supplied is necessarily limited in most instances.

According to the invention, a stuffer-box crimper, comprising a pair of nip rolls, a compression chamber, and

two bearing members each one in contact, at the location of the nip of said rolls and on opposing sides thereof, with at least the outer annular portion of the sides of both said nip rolls, is characterised in that said bearing members are each provided with means adapted continuously to cool them.

Preferably,-said means for cooling each of the bearing members consists of a circulation system for a coolant fluid. A liquid coolant, such as water, is a very convenient heat transfer medium for the purpose.

Each bearing member itself can be an intrinsic part of the circulation system, that member being, for instance, a disc insert as previously referred to. Alternatively, the system can incorporate another member, such as a backing pressure disc pressed in close contact with a disc bearing member, which other member is in cooling relationship with the bearing member.

When the circulation system is an intrinsic part of a disc insert, whether such disc insert is a pressure disc or a bearing disc, it is convenient simply to provide an annular cavity within the disc, around which the coolant fluid can circulate, the fluid being led into the cavity by a pipe through the periphery of the disc at one point and led out through another such pipe at another point spaced around the periphery from said one point.

When a cooled pressure disc is used in conjunction with a bearing disc, it is sometimes desirable that the bearing disc shall be thinner than the pressure disc. This sort of combination may be desirable on economic grounds, because the thin bearing disc, only, need be made of wear-resistant material.

One embodiment of the invention will now be described with reference to the accompanying drawings,

in which 7 FIGURE 1 is a view from above the nip rolls of a stuffer box crimper, showing the apparatus of the embodiment;-

.FIGURE 2 is a front elevation of a backing (pressure) disc for use in the embodiment; and

FIGURE 3 is a section on AA of FIGURE 2.

In FIGURE 1, arm 1 is pivotally mounted at 3 to Arm 1 is detachably secured to the frame at its other end by pivoted bolt 7 and nut 9. The arm 1 serves as a gate by which bearing discs 11, 13 are held in contact with the sides of nip rolls 15, 17 of the stuifer box at the location of the nip thereof, the bearing discs being held in contact with the nip rolls at the required pressure by adjustment of screw 19 in arm 1. The radiused tip of screw 19 fits into an indentation in backing pressure disc 21; and the opposite backing pressure disc 23 is similarly positioned and held in contact with bearing disc 13 by means of the radiused tip of stationary screw 25.

Each backing pressure disc 21, 23 is continuously cooled by circulation of water therethrough, the water Hence, the amount of external waentering by pipes 27, 29 and leaving by pipees 31, 33. Within the discs, the water circulates around annular spaces 35, 37.

The arrangement of the pipes and the annular space is shown in greater detail in FIGURES 2 and 3, although in this case the arrangement is different in small details from that shown in FIGURE 1. The compression chamber of the crimper is illustrated at 39.

In one convenient form of the above embodiment that has been usedsuccessfully in the crimping of Nylon 66 tow containing a large number of 1 /2 denier filaments for subsequent cutting to staple fibre, each Phosphor bronze bearing disc of a standard narrow-roll crimper of the general type described above, is 4 inch thick and is continuously cooled during crimping by contact with its own brass backing (pressure) disc. Each backing (pressure) disc, fitted outside the corresponding bearing disc, is inch thick and has an annular cavity inside it; and an inch-bore flexible pressure hose supplies cooling water from a supply thereof to the cavity through a hole in the upper portion of the periphery of the backing disc, and another such pipe withdraws the Water from 'a hole spaced around the upper portion of the periphery from the first hole, the flow rate being 500 cc. per disc.

We claim:

1. A stufI'er-box crimper comprising in combination (a) a pair of nip rolls leading into a compression chamber,

(b) a compression chamber,

v(c) a pair of bearing members, each one in contact, at the location of the nip of said nip rolls and on opposing sides thereof, with at least the outer annular portion of the sides of both said nip rolls, and

(d) means in cooling relationship with said bearing members, continuously to cool them.

2. A stuffer-box crimper according to claim 1 in which said means consists of a circulation system for a-liquid coolant.

3. A stutter-box crimper according to claim 2 in which further backing members hold said bearing members in contact with the sides of said nip rolls and form an intrinsic part of said circulation system.

4. A stufi'er-box crimper comprising in combination (a) a pair of nip rolls leading into a compression chamber,

(b) a compression chamber,

(c) a pair of bearing discs, each one in contact, at

the location .of the nip of said nip rolls and on opposing sides thereof, with at least the outer annular portion of the sides of both said nip rolls,

(d) a pair of pressure discs in contact and in cooling relation with the outside faces of said bearing discs, said discs having annular cavities within them forming an intrinsic part of a circulation system for a liquid coolant,

-(e) a circulation system for a liquid coolant to cool said pressure discs, and

(f) gate means to urge said pressure discs in contact with said bearing dis-cs.

References Cited by the Examiner UNITED STATES PATENTS 2,311,174 2/1-943 Hitt 28-72 3,113,367 12/1963 McGill 28-l 3,152,379 10/ 1964 Ostan 28-1 3,160,941 12/ 1964 Williamson 28-1 ROBERT R. MACKEY, Primary Examiner.

DONALD W. PARKER, Examiner.

L. K. RIMRODT, Assistant Examiner. 

1. A STUFFER-BOX CRIMPER COMPRISING IN COMBINATION (A) A PAIR OF NIP ROLLS LEADING INTO A COMPRESSION CHAMBER, (B) A COMPRESSION CHAMBER, (C) A PAIR OF BEARING MEMBERS, EACH ONE IN CONTACT, AT THE LOCATION OF THE NIP OF SAID NIP ROLLS AND ON OPPOSING SIDES THEREOF, WITH AT LEAST THE OUTER ANNULAR PORTION OF THE SIDES OF BOTH SAID NIP ROLLS, AND (D) MEANS IN COOLING RELATIONSHIP WITH SAID BEARING MEMBERS, CONTINUOUSLY TO COOL THEM. 